(46) For centuries the smoking of tobacco in cigarettes, cigars, and pipes has produced controversy over possible health hazards, but only since the 1950’s has sufficient scientific evidence accumulated to make possible a thorough evaluation of the health risk.
Scientific investigation of the relationship of smoking and health gained impetus after the beginning of the 20th century, then an increase in lung cancer was noted. As the use of tobacco increased, studies improved. (47) Although some gaps in knowledge still exist, the information now available is sufficient to permit making sound judgments, based on the converging lines of evidence.
(48) Investigators have directed their principal consideration to cigarette smoking because the health consequences attributed to it far exceed those due to smoking cigars and pipes. The widespread popularity of cigarettes is comparatively recent in man’s use of tobacco. The smoking
(46) For centuries the smoking of tobacco in cigarettes, cigars, and pipes has produced controversy over possible health hazards, but only since the 1950’s has sufficient scientific evidence accumulated to make possible a thorough evaluation of the health risk.
Scientific investigation of the relationship of smoking and health gained impetus after the beginning of the 20th century, then an increase in lung cancer was noted. As the use of tobacco increased, studies improved. (47) Although some gaps in knowledge still exist, the information now available is sufficient to permit making sound judgments, based on the converging lines of evidence.
(48) Investigators have directed their principal consideration to cigarette smoking because the health consequences attributed to it far exceed those due to smoking cigars and pipes. The widespread popularity of cigarettes is comparatively recent in man’s use of tobacco. The smoking
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